The invention relates to torsional vibration dampers particularly but not exclusively for incorporation in automobile friction clutch driven plates.
Friction clutch driven plates for motor vehicles typically comprise a friction facing carrier mounted on and capable of limited angular movement about a flanged hub, resilient means acting between the carrier and the hub flange to control the angular movement and friction damping means acting between the hub and the carrier. It is also known to provide a control means mounted for angular movement with respect to the hub and carrier and stops means limiting angular movement between the control member and one of the hub and carrier to less than the angular movement available between the hub and the carrier. A frictional interconnection between the control member and the other of the hub and carrier then comes into effect to provide frictional resistance to angular movement between the hub and the carrier after initial relative movement during which the control member moves more freely within limits controlled by the stop means.
One such construction is shown in our own Patent GB No. 2 052 683 B.
It is an object of the present invention to provide a torsional vibration damper providing controlled friction in this way but with a simplified construction.